Thin-Film Thermo-Electric Generator and Fabrication Method Thereof

ABSTRACT

A method of manufacturing a thin-film thermo-electric generator includes the steps of: forming two or more PN junctions each having a three-layer structure; forming a substrate which has a first side and an opposed second side; coupling the PN junctions at the first side of the substrate to define a first group of PN junctions at the first side of the substrate; and providing two electrodes that one of the electrodes is extracted from the first group of PN junctions. Accordingly, each of the PN junctions is formed by depositing an insulating thin-film layer between a P-type thermo-electric thin-film layer and a N-type thermo-electric thin-film layer.

CROSS REFERENCE OF RELATED APPLICATION

This is a Continuation application that claims priority to U.S.non-provisional application, application Ser. No. 13/126,076, filed Apr.26, 2011, which claims priority to international application numberPCT/CN2009/075419, international filing date Dec. 9, 2009.

NOTICE OF COPYRIGHT

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to any reproduction by anyone of the patent disclosure, as itappears in the United States Patent and Trademark Office patent files orrecords, but otherwise reserves all copyright rights whatsoever.

BACKGROUND OF THE PRESENT INVENTION

1. Field of Invention

This invention relates to thermo-electric technology, and moreparticularly to a thin-film thermo-electric generator and fabricationmethod thereof.

2. Description of Related Arts

The thermo-electric generator is a kind of generator made on the basisof Seebeck Effect, the heat energy is transformed into electric energy.The working principle of thermo-electric generator is that connectingone end of two different metals or two different types ofthermo-electric conversion materials P-type and N-type semiconductors,placing this end in high temperature condition, and placing the otherend in low temperature condition. Compared with the other end, the endin high temperature condition has better thermal activation and higherdensity of electrons and holes, the electrons and holes spread to theend in low temperature condition, thus an electric potential differenceis formed in the end in low temperature condition. Combing a number ofthis kind of thermo-electric conversion materials P-type and N-typesemiconductors to form a module supplying adequate voltage, this modulebecomes a thermo-electric generator.

The thermo-electric generator is a kind of clean, noiseless energywithout discharging any hazardous substance, having high reliability andlong useful time, and supplying long, safe, continuous and stableelectricity output. Presently the thermo-electric generator is made bycutting and welding the thermo-electric materials. There are two typesof fabrication methods. In the first method, depositing a photosensitiveresist on the same chip, then forming a P-type and N-type area throughdouble photo etching respectively, and finally depositing P-type andN-type thermo-electric materials in the P-type and N-type arearespectively. This method is difficult for application, especially forthe procedure of combining thermo-electric units in which the chip isrequired to be stripped from the deposited thermo-electric units. In thesecond method, P-type and N-type thermo-electric unit chip is separatelymanufactured, in the fabrication of micro thin-film thermo-electricgenerator, the conducting layer connecting P-type and N-typethermo-electric units can be manufactured on condition that the chip isnot stripped from the deposited thermo-electric units. This method hascomplicated procedures, and the thin-film of the thermo-electricgenerator is merely limited to single thin-film, so the performance islimited.

SUMMARY OF THE PRESENT INVENTION

To solve the above-mentioned problems, this invention provides athin-film thermo-electric generator and fabrication method thereof,improving the performance and simplifying the fabrication processes.

The technical solutions of the present invention are as follows:

A thin-film thermo-electric generator comprises a substrate, a P-typethermo-electric thin-film layer, an insulating thin-film layer and aN-type thermo-electric thin-film layer is repeatedly deposited in turnson one side of said substrate, a group of said P-type thermo-electricthin-film layer, said insulating thin-film layer and said N-typethermo-electric thin-film layer forms a three-layer structure, saidP-type thermo-electric thin-film layer and said N-type thermo-electricthin-film layer of said three-layer structure is connected in one end ofsaid insulating thin-film layer to form a PN junction, an insulatinglayer is provided between two said adjacent PN junctions, and said twoadjacent PN junctions is connected in one end of said insulating layer,in order to form a serial PN junction, an electrode is extracted fromthe outermost thin-film layer on one side of said substrate and anotherelectrode is extracted from one side of the substrate deposited bythermo-electric thin-film layer.

A thin-film thermo-electric generator, wherein the thickness range ofsaid substrate is 0.1 mm-100 mm, the thickness range of said P-typethermo-electric thin-film layer is 1 nm-10 μm, the thickness range ofsaid N-type thermo-electric thin-film layer is 1 nm-10 μm.

A thin-film thermo-electric generator, wherein the shape of saidsubstrate is regular rectangle.

A thin-film thermo-electric generator comprises a substrate, a P-typethermo-electric thin-film layer, an insulating thin-film layer and aN-type thermo-electric layer is repeatedly deposited in turns on oneside of said substrate, a group of said P-type thermo-electric thin-filmlayer, said insulating thin-film layer and said N-type thermo-electricthin-film layer forms a three-layer structure, said P-typethermo-electric thin-film layer and said N-type thermo-electricthin-film layer of said three-layer structure is connected in one end ofsaid insulating thin-film layer to form a PN junction, an insulatinglayer is provided between two said adjacent PN junctions, and said twoadjacent PN junctions is connected in one end of the insulating layer,in order to form a serial PN junction, two electrodes is respectivelyextracted from the outermost thin-film layer on two sides of saidsubstrate.

A method for fabrication a thin-film thermo-electric generator comprisessteps as follows:

selecting a substrate and sheltering one side of said substrate;

presetting an electrode on a surface of said substrate;

depositing a P-type thermo-electric thin-film layer on the side of thesubstrate on which the electrode is preset;

sheltering said substrate, one end and all sides of deposited thin-filmlayer, depositing an insulating thin-film layer on said P-typethermo-electric thin-film layer;

sheltering said substrate and all sides of deposited thin-film layer,depositing a N-type thermo-electric thin-film layer on said insulatingthin-film layer to form a three-layer structure, the P-typethermo-electric thin-film layer and N-type thermo-electric thin-filmlayer of said three-layer structure is connected in said sheltered endof the substrate to form a PN junction;

repeating above-said steps to form multiple PN junctions;

sheltering said substrate, the other end and all sides of the depositedthin-film layers, depositing an insulating thin-film layer between everytwo adjacent PN junctions, said two adjacent three-layer PN junctionsare connected in the other end of said deposited thin-film layers toform a PN junction in series:

extracting another electrode from the outermost thin-film layer of thelast three-layer PN junction, to form the main structure of a thin-filmthermo-electric generator.

A method for fabrication a thin-film thermo-electric generator,depositing multilayer on the two sides of the substrate, and furthercomprises steps as follows:

selecting a substrate and sheltering one side of said substrate;

depositing a P-type thermo-electric thin-film layer on the side of thesubstrate;

sheltering said substrate, one end and all sides of deposited thin-filmlayer, depositing an insulating thin-film layer on said P-typethermo-electric thin-film layer;

sheltering said substrate and all sides of deposited thin-film layer,depositing a N-type thermo-electric thin-film layer on said insulatingthin-film layer to form a three-layer structure, the P-typethermo-electric thin-film layer and N-type thermo-electric thin-filmlayer of said three-layer structure is connected in said sheltered endof the substrate to form a PN junction;

repeating above-said steps to form multiple PN junctions;

sheltering said substrate, the other end and all sides of the depositedthin-film layers, depositing an insulating thin-film layer between everytwo adjacent PN junctions, said two adjacent three-layer PN junctionsare connected in the other end of said deposited thin-film layers toform a PN junction in series;

extracting another electrode from the outermost thin-film layer of thelast three-layer PN junction;

repeating above-said steps to form multiple serial three-layer PNjunctions on the other side of said substrate, extracting anotherelectrode from the outermost thin-film layer of the last three-layer PNjunction on the other side of said substrate, to form the main structureof a thin-film thermo-electric generator.

For the thin-film thermo-electric generator and fabrication method ofthis invention, a P-type thermo-electric thin-film layer, an insulatingthin-film layer and a N-type thermo-electric thin-film layer isdeposited on a substrate to form a three-layer PN (Positive-Negative)junction, multiple three-layer PN junctions in series are available, aninsulating thin-film layer is provided between every to serialthree-layer PN junctions, and electrodes are extracted from thesubstrate and the outermost thin-film layer of the last three-layerthin-film PN junctions. The present invention applies the deposition ofP-type thermo-electric thin-film layer, an insulating thin-film layerand a N-type thermo-electric thin-film layer to form a three-layer PNjunction, thus thermo-electric generator is formed, during thedeposition of the insulating thin-film layer, intentionally shelteringthe substrate and one end of the deposited thin-film layer anddepositing the P-type or N-type materials on the substrate and one endof the deposited thin-film layer directly, to form a connection of PNjunction or a serial connection between two PN junction, the separateconnection of the P-type or N-type materials is not required,simplifying the fabrication processes of the thin-film thermo-electricgenerator, owning to the characteristics of the thin-filmthermo-electric materials and serial connection structure of multiplethree-layer PN junctions, the performance of the thin-filmthermo-electric generator is greatly improved.

Still further objects and advantages will become apparent from aconsideration of the ensuing description and drawings.

These and other objectives, features, and advantages of the presentinvention will become apparent from the following detailed description,the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a -FIG. 1i are the schematic diagrams of the fabrication processof the first embodiment of the invention.

FIG. 2a -FIG. 2h are the schematic diagrams of the fabrication processof the second embodiment of the invention.

FIG. 3a -FIG. 3g are the schematic diagrams of the fabrication processof the third embodiment of the invention.

FIG. 4a -FIG. 4h are the schematic diagrams of the fabrication processof the forth embodiment of the invention.

FIG. 5a -FIG. 5g are the schematic diagrams of the fabrication processof the fifth embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The following description is disclosed to enable any person skilled inthe art to make and use the present invention. Preferred embodiments areprovided in the following description only as examples and modificationswill be apparent to those skilled in the art. The general principlesdefined in the following description would be applied to otherembodiments, alternatives, modifications, equivalents, and applicationswithout departing from the spirit and scope of the present invention.

The present invention provides a thin-film thermo-electric generator andfabrication method thereof. To make the technical solutions of thepresent invention more comprehensible, the present invention isdescribed in detail with reference to the accompanying drawings andembodiments as follows.

The First Embodiment

FIG. 1a -FIG. 1i are the schematic diagrams of the fabrication processof the first embodiment of the invention. FIG. 1i is the schematicdiagrams of the end of the thin-film thermo-electric generator. In thefirst embodiment, the thin-film thermo-electric generator comprises aninsulating substrate 101, an extractive electrode 102, a P-typethermo-electric thin-film layer 103, an insulating thin-film layer 104,a N-type thermo-electric thin-film layer 105, an insulating thin-filmlayer 106, a P-type thermo-electric thin-film layer 107, an insulatingthin-film layer 108, a N-type thermo-electric thin-film layer 109, andan extractive electrode 110.

FIG. 1a shows a preset electrode 102 on a surface of the insulatingsubstrate 101.

FIG. 1b shows a P-type thermo-electric thin-film layer 103 deposited onthe side of the substrate on which the electrode is preset.

FIG. 1c shows an insulating thin-film layer 104 deposited on the P-typethermo-electric thin-film layer 103.

FIG. 1d shows a N-type thermo-electric thin-film layer 105 deposited onthe insulating thin-film layer 104.

FIG. 1e shows an insulating thin-film layer 106 deposited on the N-typethermo-electric thin-film layer 105.

FIG. 1f shows a P-type thermo-electric thin-film layer 107 deposited onthe insulating thin-film layer 106.

FIG. 1g shows an insulating thin-film layer 108 deposited on the P-typethermo-electric thin-film layer 107.

FIG. 1h shows a N-type thermo-electric thin-film layer 109 deposited onthe insulating thin-film layer 108.

FIG. 1i shows the formation of an insulating thin-film layer 116, aP-type thermo-electric thin-film layer 117, an insulating thin-filmlayer 118 and a N-type thermo-electric thin-film layer 119.

The P-type thermo-electric thin-film layer and the N-typethermo-electric thin-film layer is connected in one end of theinsulating thin-film layer to form a three-layer PN junction. Aninsulating layer is provided between two adjacent PN junctions, and thetwo adjacent PN junctions is connected in one end of the insulatinglayer, in order to form a serial PN junction. Another electrode 110 isprovided in the N-type thermo-electric thin-film layer 119 of the lastthree-layer PN junction. Thus, the main structure of thin-filmthermo-electric generator as shown in FIG. 1i is formed. Then thethin-film thermo-electric generator is made by scribing, racking,packaging and related subsequent procedures.

The general materials of the thin-film thermo-electric generator aremetal and semiconductor. The P-type and N-type thermo-electric materialsin the embodiment of this invention may be two different metals orsemiconductors made by depositing two different metal layers orsemiconductors to form a thermo-electric generator. During thefabrication process, the depositing of N-type thermo-electric layer canbe carried before or after the depositing of P-type thermo-electricthin-film layer.

Several methods can be applied to make the P-type and N-typethermo-electric thin-film layers, such as vacuum evaporation, MoleculeBeam Epitaxy (MBE), magnetron sputtering, ion beam sputteringdeposition, Laser Deposition, electrochemical atomic layer epitaxy(ECALE), metal-organic chemical vapor deposition (MOCVD), and successiveionic layer adsorption and reaction (SILAR). The first embodiment of theinvention provides a fabrication process of the thin-filmthermo-electric generator with the ion beam sputtering deposition:

The device is an ultrahigh vacuum ion beam sputtering deposition system.Selecting targets of P-type and N-type metals S.sub.b, B.sub.i andinsulating material Al₂O₃, the purity of the target is 99.99%, andsetting these targets in the target position respectively. Conductingultrasonic washing on the substrate of common soda-lime glass, and putit in clamping fixture in the deposition room. The fixture may furtherhave apparatuses for intentional sheltering in the two ends and thesides. In the room temperature, the deposition is carried by adjustingthe targets and ion beam sputtering deposition, the procedures is asbelow:

Step 1: as shown in FIG. 1 a, sheltering all sides of the glasssubstrate 101 other than in the area of the preset electrode 102.

Step 2: as shown in FIG. 1 b, depositing a 300 nm thick S_(b) thin-filmlayer 103 on the side of the substrate 101 on which the electrode ispreset.

Step 3: as shown in FIG. 1 c, sheltering the substrate 101, one end andall sides of the S_(b) thin-film layer 103, and depositing a 500 nmthick Al₂O₃ thin-film layer 104 on the S_(b) thin-film layer 103.

Step 4: as shown in FIG. 1 d, sheltering the substrate 101 and all sidesof the deposited thin-film layers, and depositing a 300 nm thick B_(i)thin-film layer 105 on the deposited Al₂O₃ thin-film layer 104, theS_(b) thin-film layer 103 and the Bi thin-film layer 105 is connected inone end of the Al₂O₃ thin-film layer 104 to form the first PN junction.

Step 5: as shown in FIG. 1 e, sheltering the substrate 101 and all sidesof the deposited thin-film layers, and depositing a 500 nm thick Al₂O₃thin-film layer 106 on the Bi thin-film layer 105.

Step 6: as shown in FIG. 1 f, sheltering the substrate 101 and all sidesof the deposited thin-film layers, and depositing a 300 nm thick S_(b)thin-film layer 107 on the Al₂O₃ thin-film layer 106, the S_(b)thin-film layer 107 and the B_(i) thin-film layer 105 is connected inone end of the Al₂O₃ thin-film layer 106 to form a connecting portbetween the first and the second PN junction.

Step 7 as shown in FIG. 1 g, sheltering the substrate 101, one end andall sides of the deposited thin-film layers, and depositing a 500 nmthick Al₂O₃ thin-film layer 108 on the S_(b) thin-film layer 107.

Step 8: as shown in FIG. 1 h, sheltering the substrate 101 and all sidesof the deposited thin-film layers, and depositing a 300 nm thick B_(i)thin-film layer 109 on the Al₂O₃ thin-film layer 108, the S_(b)thin-film layer 107 and the B_(i) thin-film layer 109 is connected inone end of the Al₂O₃ thin-film layer 108 to form a second PN junction.The first and the second PN junction is connected in series through theAl₂O₃ thin-film layer 106.

Step 9: as shown in FIG. 1 i, repeating the steps from Step 5 to Step 8to form a Al₂O₃ thin-film layer 116, a S_(b) thin-film layer 117, aAl₂O₃ thin-film layer 118, and a B_(i) thin-film layer 119 respectively,accordingly a connection in series between a PN junction and a depositedPN junction is made, the connection of multiple three-layer PN junctionsin series is available, an insulating layer is set among everythree-layer PN junctions. During the deposition, the background vacuumdegree is 4.5×10⁻⁴ Pa, the working vacuum degree is 4.1×10⁻² Pa, and theworking gas is 99.99% pure Ar with a rate of flow of 4 sccm. Thetechnical parameters of the ion beam sputtering deposition are as below:plate voltage 1 KV, anode voltage 75V, acceleration voltage 220V,cathode voltage 7V, cathode current 11 A, and beam 14 mA. Afterobtaining one or multiple three-layer PN junctions in series bydepositing on the substrate 101, another electrode 110 is extracted fromthe B.sub.i thin-film layer 119 in the last PN junction, thus the mainstructure of the thin-film thermo-electric generator as shown in FIG. 1iis formed.

During the above-said fabrication process, the depositing of N-typethermo-electric thin-film layer can be carried before or after thedepositing of P-type thermo-electric thin-film layer.

In the first embodiment of this invention, the fabrication processes ofthin-film thermo-electric generator with the magnetron sputtering are asbelow:

The device is a three-target magnetron sputtering system. Selectingtargets of metals S_(b), B_(i) and Al, the purity of the target is99.99%, and setting these targets in the target position respectively.Conducting ultrasonic washing on the substrate of common soda-limeglass, and put it in fixture in the deposition room. The fixture mayfurther have apparatuses for intentional sheltering in the two ends andthe sides. In the room temperature, during the deposition, thebackground vacuum is 4.5×10⁻³ Pa, the working vacuum is 4.1×10⁻² Pa.During the deposition of S_(b) and B_(i) thin-film layer with DCmagnetron sputtering, the working gas is 99.99% pure Ar with a rate offlow of 50 sccm. During the deposition of the Al₂O₃ thin-film layer withdirect current magnetron reactive sputtering, the working gas is 99.99%pure Ar with a rate of flow of 50 sccm and the reactive gas 99.99% pureO2 with a rate of flow of 50 sccm. The processes of deposition aredescribed as follows:

Step 1: as shown in FIG. 1 a, sheltering all sides of the glasssubstrate 101 other than in the area of the preset electrode 102.

Step 2: as shown in FIG. 1 b, depositing a 300 nm thick S_(b) thin-filmlayer 103 n the side of the substrate 101 on which the electrode ispreset.

Step 3: as shown in FIG. 1 c, sheltering the substrate 101, one end andall sides of the S_(b) thin-film layer 103, and depositing a 500 nmthick Al₂O₃ thin-film layer 104 on the S_(b) thin-film layer 103.

Step 4: as shown in FIG. 1 d, sheltering the substrate 101 and all sidesof the deposited thin-film layers, and depositing a 300 nm thick B_(i)thin-film layer 105 on the deposited Al₂O₃ thin-film layer 104, theS_(b) thin-film layer 103 and the B_(i) thin-film layer 105 is connectedin one end of the Al₂O₃ thin-film layer 104 to form the first PNjunction.

Step 5: as shown in FIG. 1 e, sheltering the substrate 101 and all sidesof the deposited thin-film layers. and depositing a 500 nm thick Al₂O₃thin-film layer 106 on the B_(i) thin-film layer 105.

Step 6: as shown in FIG. 1 f, sheltering the substrate 101 and all sidesof the deposited thin-film layers, and depositing a 300 nm thick S_(b)thin-film layer 107 on the Al₂O₃ thin-film layer 106, the S_(b)thin-film layer 107 and the B_(i) thin-film layer 105 is connected inone end of the Al₂O₃ thin-film layer 106 to form a connecting portbetween the first and the second PN junction.

Step 7 as shown in FIG. 1 g, sheltering the substrate 101, one end andall sides of the deposited thin-film layers, and depositing a 500 nmthick Al₂O₃ thin-film layer 108 on the S_(b) thin-film layer 107.

Step 8: as shown in FIG. 1 h, sheltering the substrate 101 and all sidesof the deposited thin-film layers, and depositing a 300 nm thick B_(i)thin-film layer 109 on the Al₂O₃ thin-film layer 108, the S.sub.bthin-film layer 107 and the B_(i) thin-film layer 109 is connected inone end of the Al₂O₃ thin-film layer 108 to form a second PN junction.The first and the second PN junction is connected in series through theAl₂O₃ thin-film layer 106.

Step 9: as shown in FIG. 1 i, repeating the steps from Step 5 to Step 8to form a Al.sub.2O.sub.3 thin-film layer 116, a S_(b) thin-film layer117, a Al₂O₃ thin-film layer 118, and a B_(i) thin-film layer 119respectively, accordingly a connection in series between a PN junctionand a deposited PN junction is made, the connection of multiplethree-layer PN junctions in series is available, an insulating layer isset among every three-layer PN junctions. During the deposition, thebackground vacuum is 4.5×10⁻⁴ Pa, the working vacuum is 4.1×10⁻³ Pa, andthe working gas is 99.99% pure Ar with a rate of flow of 4 sccm. Thetechnical parameters of the ion beam sputtering deposition are as below:plate electrode voltage 1 KV, anode voltage 75V, acceleration voltage220V, cathode voltage 7V, cathode current 11 A, and beam 14 mA. Afterobtaining one or multiple three-layer PN junctions in series bydepositing on the substrate 101, another electrode 110 is extracted fromthe B_(i) thin-film layer 119 in the last PN junction, thus the mainstructure of the thin-film thermo-electric generator as shown in FIG. 1iis formed.

During the above-said fabrication process, the depositing of N-typethermo-electric thin-film layer can be carried before or after thedepositing of P-type thermo-electric thin-film layer.

Second Embodiment

The thin-film thermo-electric generator can be made by using theinsulating substrate as well as the substrate of P-type thermo-electricmaterial (or metal) or N-type thermo-electric material (or metal). Ifthe substrate of P-type thermo-electric material is applied, thecross-section diagram of the thin-film thermo-electric generator isshown in FIG. 2 h. In this embodiment, the thin-film thermo-electricgenerator comprises a P-type thermo-electric material substrate 201, aninsulating thin-film layer 202, a N-type thermo-electric thin-film layer203, an insulating thin-film layer 204, a P-type thermo-electricthin-film layer 205, an insulating thin-film layer 206, a N-typethermo-electric thin-film layer 207, an extractive electrode 208 and anextractive electrode 209.

FIG. 2a shows the insulating thin-film layer 202 deposited on the P-typethermo-electric material substrate 201.

FIG. 2b shows the N-type thermo-electric thin-film layer 203 depositedon the insulating thin-film layer 202.

FIG. 2c shows the insulating thin-film layer 204 deposited on the N-typethermo-electric thin-film layer 203.

FIG. 2d shows the P-type thermo-electric thin-film layer 205 depositedon the insulating thin-film layer 204.

FIG. 2e shows the insulating thin-film layer 206 deposited on the P-typethermo-electric thin-film layer 205.

FIG. 2f shows the N-type thermo-electric thin-film layer 207 depositedon the insulating thin-film layer 206.

FIG. 2g shows the formation of an insulating thin-film layer 214, aP-type thermo-electric thin-film layer 215, an insulating thin-filmlayer 216 and a N-type thermo-electric thin-film layer 217.

In order to form a connection of a PN junction and a deposited PNjunction in series, multiple connections of three-layer PN junctions inseries may be applied, and an insulating thin-film layer is appliedamong the PN junctions. The three-layer P-type thermo-electric thin-filmlayer and the N-type thermo-electric thin-film layer is connected in oneend of the insulating thin-film layer to form a PN junction. Aninsulating layer is provided between two adjacent PN junctions, and thetwo adjacent three-layer PN junctions is connected in one end of theinsulating layer, in order to form a serial PN junction. An electrode208 is provided in the N-type thermo-electric thin-film layer 217 of thelast three-layer PN junction, an electrode 209 is provided in the sidewhich is not deposited in the P-type thermo-electric material substrate201. Thus, the main structure of the thin-film thermo-electric generatorbased on the P-type thermo-electric material substrate as shown in FIG.2h is formed.

For the improvement of second embodiment, if the N-type thermo-electricmaterial is applied as the substrate, the fabrication process of theN-type thermo-electric thin-film layer and the P-type thermo-electricthin-film layer shall be exchanged.

The Third Embodiment

The embodiment of the present invention has some other variations. Forexample, based on the structure of thin-film thermo-electric generatorapplying P-type thermo-electric material as the substrate as shown inFIG. 2 g, depositing multiple connections in series of three-layer PNjunctions on the other side of the P-type thermo-electric substrate 201,an insulating thin-film layer is provided between every three-layer PNjunction, to form a thin-film thermo-electric generator provided in thethird embodiment. As shown in FIG. 3 g, the thin-film thermo-electricgenerator in this embodiment comprises a substrate 301 of P-typethermo-electric material as the base of thin-film thermo-electricgenerator structure, an insulating thin-film layer 302, a N-typethermo-electric thin-film layer 303, an insulating thin-film layer 304,a P-type thermo-electric thin-film layer 305, an extractive electrode208 and an extractive electrode 209.

FIG. 3a shows a substrate 301 of P-type thermo-electric material as thebase of thin-film thermo-electric generator structure in the FIG. 2 g.

FIG. 3b shows an insulating thin-film layer 302 deposited on the otherside of the substrate 301 of P-type thermo-electric material as the baseof thin-film thermo-electric generator structure in the secondembodiment of this invention.

FIG. 3c shows a N-type thermo-electric thin-film layer 303 deposited onthe insulating thin-film layer 302.

FIG. 3d shows the insulating thin-film layer 304 deposited on the N-typethermo-electric thin-film layer 303.

FIG. 3e shows the P-type thermo-electric thin-film layer 305 depositedon the insulating thin-film layer 304.

FIG. 3f shows the formation of an insulating thin-film layer 312, aP-type thermo-electric thin-film layer 313, an insulating thin-filmlayer 314 and a N-type thermo-electric thin-film layer 315. Multipleconnections of three-layer PN junctions in series are available, aninsulating thin-film is applied between every PN junctions. Thethree-layer P-type thermo-electric thin-film layer and N-typethermo-electric thin-film layer is connected in one end of theinsulating thin-film layer, to form a PN junction. An insulatingthin-film layer is applied between every PN junction, and the PNjunctions are connected in one end of the insulating thin-film layer, toform connections of PN junctions in series.

An electrode 306 and an electrode 307 is extracted from the N-typethermo-electric thin-film layer of the last three-layer PN junction inthe two sides of the P-type thermo-electric thin-film substrate to formthe main structure of the thin-film thermo-electric generator depositedon the two-side P-type thermo-electric thin-film substrate.

For the improvement of the third embodiment, if the N-typethermo-electric material is applied as the substrate, the fabricationprocess of the N-type thermo-electric thin-film layer and the P-typethermo-electric thin-film layer shall be exchanged.

The Fourth Embodiment

The thin-film thermo-electric generator based on insulating substrate inthe first embodiment may have the structure as follows:

FIG. 4h is the cross-section view of the thin-film thermo-electricgenerator of this invention, which comprises an insulating substrate401, a P-type thermo-electric thin-film layer 402, a N-typethermo-electric thin-film layer 403, an insulating thin-film layer 404,a P-type thermo-electric thin-film layer 405, an insulating thin-filmlayer 406, a N-type thermo-electric thin-film layer 407, an extractiveelectrode 408 and an extractive electrode 409.

FIG. 4a shows the P-type thermo-electric thin-film layer 402 depositedon one side of the insulating substrate 401;

FIG. 4b shows the N-type thermo-electric thin-film layer 403 depositedon the other side of the insulating substrate 401;

FIG. 4c shows the insulating thin-film layer 404 deposited on the N-typethermo-electric thin-film layer 403;

FIG. 4d shows the P-type thermo-electric thin-film layer 405 depositedon the insulating thin-film layer 404;

FIG. 4e shows the insulating thin-film layer 406 deposited on the P-typethermo-electric thin-film layer 405;

FIG. 4f shows N-type thermo-electric thin-film layer 407 deposited onthe insulating thin-film layer 406;

FIG. 4g shows the formation of an insulating thin-film layer 414, aP-type thermo-electric thin-film layer 415, an insulating thin-filmlayer 416 and a N-type thermo-electric thin-film layer 417. Multipleconnections of three-layer PN junctions in series are available, aninsulating thin-film is applied between every PN junctions. Thethree-layer P-type thermo-electric thin-film layer and N-typethermo-electric thin-film layer is connected in one end of theinsulating thin-film layer, to form a PN junction. An insulatingthin-film layer is applied between every PN junction, and the PNjunctions are connected in one end of the insulating thin-film layer, toform connections of PN junctions in series. An electrode 408 and anelectrode 409 is extracted from the N-type thermo-electric thin-filmlayer of last three-layer PN junction on the two sides of the insulatingsubstrate.

The Fifth Embodiment

Based on the structure of thin-film thermo-electric generator applyingP-type thermo-electric material as the substrate as shown in FIG. 4 g,depositing multiple connections in series of three-layer PN junctions onthe other side of the P-type thermo-electric substrate, an insulatingthin-film layer is provided between every three-layer PN junctions, toform a thin-film thermo-electric generator provided in the thirdembodiment. As shown in FIG. 5 g, the thin-film thermo-electricgenerator in this embodiment comprises a base 501 of the thin-filmthermo-electric generator structure shown in FIG. 4 g, an insulatingthin-film layer 502, a N-type thermo-electric thin-film layer 503, aninsulating thin-film layer 504, a P-type thermo-electric thin-film layer505, an extractive electrode 506 and an extractive electrode 507.

FIG. 5a shows the base 501 of the thin-film thermo-electric generator;

FIG. 5b shows an insulating thin-film layer 502 deposited on the base501 of the P-type thermo-electric thin-film layer in the other side ofthe substrate of the thin-film thermo-electric generator as shown inFIG. 4 g;

FIG. 5c shows the N-type thermo-electric thin-film layer 503 depositedon the insulating thin-film layer 502;

FIG. 5d shows the insulating thin-film layer 504 deposited on the N-typethermo-electric thin-film layer 503;

FIG. 5e shows the P-type thermo-electric thin-film layer 505 depositedon the insulating thin-film layer 504;

FIG. 5f shows the formation of an insulating thin-film layer 512, aP-type thermo-electric thin-film layer 513, an insulating thin-filmlayer 514 and a N-type thermo-electric thin-film layer 515. Multipleconnections of three-layer PN junctions in series are available, aninsulating thin-film is applied between every PN junctions. Thethree-layer P-type thermo-electric thin-film layer and N-typethermo-electric thin-film layer is connected in one end of theinsulating thin-film layer, to form a PN junction. An insulatingthin-film layer is applied between every PN junction, and the PNjunctions are connected in one end of the insulating thin-film layer, toform connections of PN junctions in series.

An electrode 506 and an electrode 507 is extracted from the N-typethermo-electric thin-film layer of last three-layer PN junction on thetwo sides of the insulating substrate. Thus, the main structure of thethin-film thermo-electric generator two-sides deposited on the P-typethermo-electric material substrate as shown in FIG. 5g is formed.

During the above-said fabrication process in the fifth embodiment, thedepositing of N-type thermo-electric thin-film layer can be carriedbefore or after the depositing of P-type thermo-electric thin-filmlayer.

In all the above-said embodiments, the substrate can be regular arectangle or a square or in any irregular shapes. The common thicknessrange of the substrate is from 0.1 mm to 100 mm. The substrate can be aninsulating substrate, a P-type thermo-electric thin-film or a N-typethermo-electric thin-film substrate, or any other material substrate.The P-type and N-type thermo-electric thin-film materials in thethin-film thermo-electric generator can be the same or different, thisis, in the whole thin-film thermo-electric generator, the PN junctioncan be made by two different metal thin-film layer and insulating layer,and can also be made by a pair of P-type and N-type thermo-electricthin-film layers and insulating layer. During the deposition ofinsulating layers, one end of them is deliberately sheltered. Wherein,the ion beam sputtering deposition and magnetron sputtering in the firstembodiment can also be applied in the second, third, fourth and fifthembodiment, and some other methods such as vacuum evaporation, MoleculeBeam Epitaxy (MBE), Laser Deposition, electrochemical atomic layerepitaxy (ECALE), metal-organic chemical vapor deposition (MOCVD), andsuccessive ionic layer adsorption and reaction (SILAR) can be applied.Then the thin-film thermo-electric generator is made by scribing,racking, packaging and related subsequent procedures.

Thermo-electric phenomenon is reversible, and the semiconductorthermo-electric generation and refrigeration can be reversible. For asingle PN junction, if the temperature difference is used forelectricity generation, then the electricity can be used forrefrigeration in the other end. Thus, the main thin-film thermo-electricgenerator structure can be the main structure of the thin-filmthermo-electric cooler. The invention may be embodied in other specificform without departing from the spirit or essential characteristicsthereof. The present embodiments are therefore to be considered in allrespects as illustrative and not restrictive, the scope of the inventionbeing indicated by the appended claims rather than by the foregoingdescription and all changes which come within the meaning and range ofequivalency of the claims are therefore intended to be embraced therein.

One skilled in the art will understand that the embodiment of thepresent invention as shown in the drawings and described above isexemplary only and not intended to be limiting.

It will thus be seen that the objects of the present invention have beenfully and effectively accomplished. The embodiments have been shown anddescribed for the purposes of illustrating the functional and structuralprinciples of the present invention and is subject to change withoutdeparture from such principles. Therefore, this invention includes allmodifications encompassed within the spirit and scope of the followingclaims.

What is claimed is:
 1. A method of manufacturing a thin-filmthermo-electric generator, comprising the steps of: (a) forming two ormore PN junctions each having a three-layer structure, wherein each ofsaid PN junctions is formed by a step of depositing an insulatingthin-film layer between a P-type thermo-electric thin-film layer and aN-type thermo-electric thin-film layer; (b) forming a substrate, whichis a glass substrate, having a first side and an opposed second side;(c) coupling said PN junctions at said first side of said substrate todefine a first group of PN junctions at said first side of saidsubstrate; and (d) providing two electrodes that one of said electrodesis extracted from said first group of PN junctions.
 2. The method, asrecited in claim 1, wherein the step (c) further comprises a step ofcoupling said PN junctions at said second side of said substrate todefine a second group of PN junctions at said second side of saidsubstrate.
 3. The method as recited in claim 2 wherein, in the step (d),another said electrode is extracted from said second group of PNjunctions.
 4. The method, as recited in claim 2, wherein the step (c)further comprises the steps of: (c.1) orderly connecting two or more ofsaid PN junctions in series to form said first group of PN junctions tobe coupled at said first side of said substrate; and (c.2) orderlyconnecting two or more of said PN junctions in series to form saidsecond group of PN junctions to be coupled at said second side of saidsubstrate.
 5. The method, as recited in claim 3, wherein the step (c)further comprises the steps of: (c.1) orderly connecting two or more ofsaid PN junctions in series to form said first group of PN junctions tobe coupled at said first side of said substrate; and (c.2) orderlyconnecting two or more of said PN junctions in series to form saidsecond group of PN junctions to be coupled at said second side of saidsubstrate.
 6. The method, as recited in claim 2, wherein two of saidinsulating thin-film layers in said first and second groups of PNjunctions are identical and are connected to said first and second sidesof said substrate respectively.
 7. The method, as recited in claim 5,wherein two of said insulating thin-film layers in said first and secondgroups of PN junctions are identical and are connected to said first andsecond sides of said substrate respectively.
 8. The method, as recitedin claim 3, wherein the step (d) further comprises the steps of: (d.1)extracting one of said electrodes from said N-type thermo-electricthin-film layer at the outermost position of said first group of PNjunction; and (d.2) extracting another said electrode from said N-typethermo-electric thin-film layer at the outermost position of said secondgroup of PN junction.
 9. The method, as recited in claim 5, wherein thestep (d) further comprises the steps of: (d.1) extracting one of saidelectrodes from said N-type thermo-electric thin-film layer at theoutermost position of said first group of PN junction; and (d.2)extracting another said electrode from said N-type thermo-electricthin-film layer at the outermost position of said second group of PNjunction.
 10. The method, as recited in claim 7, wherein the step (d)further comprises the steps of: (d.1) extracting one of said electrodesfrom said N-type thermo-electric thin-film layer at the outermostposition of said first group of PN junction; and (d.2) extractinganother said electrode from said N-type thermo-electric thin-film layerat the outermost position of said second group of PN junction.
 11. Themethod, as recited in claim 1, wherein in each of said PN junctions,said P-type thermo-electric thin-film layer and said N-typethermo-electric thin-film layer are connected at one end in said PNjunction while said insulating thin-film layer is provided at anotherend in said PN junction and is partially provided between said P-typethermo-electric thin-film layer and said N-type thermo-electricthin-film layer.
 12. The method, as recited in claim 3, wherein in eachof said PN junctions, said P-type thermo-electric thin-film layer andsaid N-type thermo-electric thin-film layer are connected at one end insaid PN junction while said insulating thin-film layer is provided atanother end in said PN junction and is partially provided between saidP-type thermo-electric thin-film layer and said N-type thermo-electricthin-film layer.
 13. The method, as recited in claim 10, wherein in eachof said PN junctions, said P-type thermo-electric thin-film layer andsaid N-type thermo-electric thin-film layer are connected at one end insaid PN junction while said insulating thin-film layer is provided atanother end in said PN junction and is partially provided between saidP-type thermo-electric thin-film layer and said N-type thermo-electricthin-film layer.
 14. The method, as recited in claim 1, wherein athickness range of said substrate is 0.1 mm-100 mm, a thickness range ofsaid P-type thermo-electric thin-film layer is 1 nm-10 μm, a thicknessrange of said N-type thermo-electric thin-film layer is 1 nm-10 μm. 15.The method, as recited in claim 3, wherein a thickness range of saidsubstrate is 0.1 mm-100 mm, a thickness range of said P-typethermo-electric thin-film layer is 1 nm-10 μm, a thickness range of saidN-type thermo-electric thin-film layer is 1 nm-10 μm.
 16. The method, asrecited in claim 3, wherein a shape of said substrate is regularrectangle, wherein said two electrodes respectively extracted from saidPN junctions of said first and second groups of PN junctions at theoutermost positions from said substrate respectively.
 17. The method, asrecited in claim 15, wherein a shape of said substrate is regularrectangle, wherein said two electrodes respectively extracted from saidPN junctions of said first and second groups of PN junctions at theoutermost positions from said substrate respectively.
 18. The method, asrecited in claim 1, wherein the step (d) further comprises the steps of:(d.1) extracting one of said electrodes from said N-type thermo-electricthin-film layer at the outermost position of said first group of PNjunction; and (d.2) extracting another said electrode from said secondside of said substrate.
 19. The method, as recited in claim 18, whereinin each of said PN junctions, said P-type thermo-electric thin-filmlayer and said N-type thermo-electric thin-film layer are connected atone end in said PN junction while said insulating thin-film layer isprovided at another end in said PN junction and is partially providedbetween said P-type thermo-electric thin-film layer and said N-typethermo-electric thin-film layer.
 20. The method, as recited in claim 19,wherein a thickness range of said substrate is 0.1 mm-100 mm, athickness range of said P-type thermo-electric thin-film layer is 1nm-10 μm, a thickness range of said N-type thermo-electric thin-filmlayer is 1 nm-10 μm.